Dimmer Levels - Dumb Bulbs or GE zwave Dimmer switch - Which one has the most effect on level

I have a good amount of LED recessed inserts mostly controled by various GE Zwave dimmer switches. A few different GE models of switch, all the same LED inserts. I dont feel like the bulbs really dim as much as I’d like. Is it typically the switches, or the LED bulbs that make the most difference in how low they can dim.